1. Field of the Invention
The present invention relates to an image forming apparatus in which toner images are formed on a plurality of image carrying bodies and successively transferred to a transfer material such as paper, thereby forming a multicolor image.
2. Description of the Related Art
In recent years, color copying machines have been put into practical use to meet a demand for colored documents in the office. A copying machine having four serial photosensitive drums is known as one of the color copying machines. In this type of copying machine, four photoconductive drums are arranged in parallel with one another, and four toner images are individually formed on the drums with yellow, magenta, cyan and black toners, and consecutively transferred to a transfer material.
Thus, in the four-drum copying machine, since toner images individually formed on the four drums are consecutively transferred to a transfer material, a plurality of image forming sections respectively including the photoconductive drums must be arranged in parallel with each other. If the image forming sections are not parallel with a satisfactory accuracy, the obtained color image will have color deviation.
To prevent this, in a conventional color copying machine, as disclosed in Jpn. Pat. Appln. KOKAI Publication No. 64-84263, one axial end portion of each of the image forming sections is attached to a fixed position on a body frame located on the rear side of the copying machine main body, while the other axial end portion thereof is fixed to a body frame located on the front side of the main body via a position-adjustable supporting member. Upon assembling the copying machine, the plurality of image forming sections are provisionally attached to the body frames, and in this state, the copying machine is operated to actually form a color image. The degree of parallelism of the image forming sections is adjusted by changing the positions of the supporting members, while the state of color deviation is being observed. After the adjustment is completed, the supporting members are immovably fixed to the body frames. Thus, the assembly of the image forming sections is finished.
As described above, the conventional color copying machine is disadvantageous in that the assembly is difficult and very time-consuming, since a plurality of image forming sections must be fixed to body frames, while the positions thereof being individually adjusted.